Chelsea have been heavily pursuing Everton defender John Stones, but their first bid of £20m was rejected.
According to the Daily Mirror, Manchester United are now jumping into the race for the 21-year-old defender.
Man United are hoping to capitalise on Martinez’s distain for Chelsea boss Jose Mourinho making the negotiations public.
Although Everton are reluctant and in no hurry to sell Stones, Chelsea have vowed to come back with an improved offer that’s expected to be worth £38m.
Man United have increased their options for a top-notch defender to sign for the 2015-16 season.
They are also heavily pursuing Real Madrid defender Sergio Ramos and Valencia defender Nicolas Otamendi.
Stones may be the most ideal option for the Red Devils, as he is much younger than Otamendi and Ramos.
United appear to have a leg up on Chelsea as well since Martinez has become angry with Mourinho.
However, United signing Stones may not come to fruition. Real Madrid have given the Red Devils the green light to acquire Ramos if they offer at least £50m.